Mechanical properties and microstructural characterization of Al-5083 mechanically alloyed powders consolidated through ECAP process

Abstract

Equal channel angular pressing (ECAP) is used to consolidate particles of nano and micro levels at a shorter time and lower temperature. This process is more convenient than the conventional sintering process. In the conventional route, the sintered density obtained is 2.36 g/cc (89% relative density). Whereas, in ECAP, the theoretical density of 93% is observed after the first pass which is higher than the conventionally sintered sample. The relative density increases with an increase in the number of passes and it reached a maximum of 98.5% after 3 passes in route BC. The microstructure of the conventionally sintered sample showed coarse grains with the presence of porosity. Whereas, the samples compacted by ECAP had fine and elongated grains along with a low amount of porosity. Hardness showed a similar pattern to that of density. In ECAP, a hardness of 81 HRB was obtained after three passes in route BC. Al-5083 alloy was compacted by ECAP at 150°C with back pressure (50 MPa). No surface and internal defects were observed. The relative density of 98.5% without any surface cracks was obtained after three passes in route BC when processed through ECAP.